The distribution of city populations has attracted much attention, in part because it constrains models of local growth. However, there is no consensus on the distribution below the very upper tail, because available data need to rely on “legal” rather than “economic” definitions for medium and small cities. To remedy this difficulty, we construct cities “from the bottom up” by clustering populated areas obtained from high-resolution data. We find that Zipf 's law for population holds for cities as small as 5,000 inhabitants in Great Britain and 12,000 inhabitants in the US. We also find a Zipf 's law for areas. JEL: R11, R12, R23

Major League Baseball umpires express their racial/ethnic prefer ences when they evaluate pitchers. Strikes are called less often if the umpire and pitcher do not match race/ethnicity, but mainly where there is little scrutiny of umpires. Pitchers understand the incentives and throw pitches that allow umpires less subjective judgment (e.g., fastballs over home plate) when they anticipate bias. These direct and indirect effects bias performance measures of minorities downward. The results suggest how discrimination alters discriminated groups' behavior generally. They imply that biases in measured productivity must be accounted for in generating measures of wage discrimination.

Inputs and Impacts in Charter Schools: KIPP Lynn by Joshua D. Angrist, Susan M. Dynarski, Thomas J. Kane, Parag A. Pathak and Christopher R. Walters. Published in volume 100, issue 2, pages 239-43 of American Economic Review, May 2010

Examining the Role of Social Isolation on Stated Preferences by John A. List, Robert P. Berrens, Alok K. Bohara and Joe Kerkvliet. Published in volume 94, issue 3, pages 741-752 of American Economic Review, June 2004

We study the residential choice of siblings who are altruistic towards their parents. The first-born child’s location choice influences the behavior of the second-born child and can shift some of the burden of providing care for the parents from one child to the other. These strategic considerations lead to an equilibrium location pattern with firstborn children locating further away from their parents than second-born children. We also analyze the location choices empirically using German data. These data confirm our theoretical predictions.

Anomalous Behavior in a Traveler's Dilemma? by C. Monica Capra, Jacob K. Goeree, Rosario Gomez and Charles A. Holt. Published in volume 89, issue 3, pages 678-690 of American Economic Review, June 1999

This paper analyzes the effect on performance and earnings of delegating the wage choice to employees. Our results show that such delegation significantly increases effort levels. Moreover, we observe a Pareto improvement, as the earnings of both employers and employees increase when employers delegate than when they do not. Interestingly, we also find that the employees' performance under delegation is higher than under nondelegation, even for similar wages. While there is strong evidence that behavior reflects strategic considerations, this result also holds for one-shot interactions. A possible nonstrategic motivation explaining the positive reaction to delegation is a sense of enhanced responsibility.

We propose a novel identification strategy to isolate exogenous immigration shocks across US counties, by interacting quasi-random variations in the composition of ancestry across counties with the contemporaneous inflow of migrants from different countries. We show a positive causal impact of immigration on local innovation and wages at the five-year horizon. The positive dynamic impact of immigration on innovation and wages dominates the short-run negative impact of increased labor supply. A structural estimation of a model of endogenous growth and migrations suggests the increased immigration to the United States since 1965 may have increased innovation and wages by 5 percent.

We explore how access to modern hospitals and medicine affects mortality by leveraging efforts of the Duke Endowment to modernize hospitals in the early twentieth century. The Endowment helped communities build and expand hospitals, obtain state-of-the-art medical technology, attract qualified medical personnel, and refine management practices. We find that Duke support increased the size and quality of the medical sector, fostering growth in not-for-profit hospitals and high-quality physicians. Duke funding reduced both infant mortality—with larger effects for Black infants than White infants—and long-run mortality. Finally, we find that communities aided by Duke benefited more from medical innovations.

To investigate barriers to universal health insurance in developing countries, we designed a randomized experiment involving about 6,000 households in Indonesia who are subject to a government health insurance program with a weakly enforced mandate. Time-limited subsidies increased enrollment and attracted lower-cost enrollees, in part by reducing the strategic timing of enrollment to correspond with health needs. Registration assistance also increased enrollment, but increased attempted enrollment much more, as over one-half of households who attempted to enroll did not successfully do so. These findings underscore how weak administrative capacity can create important challenges in developing countries for achieving widespread coverage.